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Spatiotemporal variability on multi-decadal time scales can be observed in weather conditions associated with wildfires. The climatic factors that drive this variability in fire weather conditions have been studied using bias-corrected 20th Century Reanalysis data of the mean state and extreme values of the McArthur Forest Fire Danger Index (FFDI) from 1876 to 2014. In particular, the association of this time series with the climate drivers of El Niño-Southern Oscillation (ENSO), Indian Ocean Dipole (IOD) and Southern Annular Mode (SAM) are analysed using several techniques. The potential for long-term changes in the relationships between the climate drivers and seasonal FFDI values is also explored by breaking the total time period into two epochs. Composite analysis was performed to separate the phases of ENSO, IOD and SAM (given their interrelationships) and determine which phase combinations influence severe fire weather conditions the most. The most severe fire weather conditions were observed during a specific combination of ENSO, IOD and SAM phases, with results mapped to show spatial and seasonal variations in this over Australia. Long-term changes in the relationships between fire weather conditions and the three climate drivers (ENSO, IOD and SAM) are documented. These findings are based on a longer time period than similar previous studies, intended to help contribute to the range of guidance available for long-range fire weather outlooks and enhanced decision-making for fire agencies. [ABSTRACT FROM AUTHOR]

For the first time, the secondary diamond nucleation processes are compared during the growth of polycrystalline diamond films by the MPCVD method with addition of nitrogen and ammonia. An ammonia molecule (NH3) has a lower ionization energy than a nitrogen molecule (N2) in microwave plasma. It has been established that when using ammonia, the transition to the nanocrystalline structure of diamond occurs at significantly lower concentrations than when using nitrogen. [ABSTRACT FROM AUTHOR]

World-wide introduction of high throughput screening (HTS) methods in drug discovery research did not result in the increased number of novel medications on the market. We discuss novel trends in drug discovery that came from the understanding that majority of diseases are multifactorial and that one enzyme has many protein substrates. Hence, new approaches are focused on development of drugs, which (1) trigger survival pathways to return the organism to homeostatic balance, and (2) inhibit enzymes modifying histones or transcription factors not at the active site, but by displacement of protein substrates from the enzyme complexes. A good example for both approaches comes from the development of activators of antioxidant defense. We analyze and illustrate problems of commonly used in vitro HTS assays, and briefly discuss advantages and limitations of small animal models. The novel approaches are complementary to the standard HTS and do not substitute for testing in mammals. Development of transgenic reporter mice to monitor drug effects by means of in vivo imaging is extremely promising to select proper dosage and administration regimes for full-range PK studies. [ABSTRACT FROM AUTHOR]

The chemical vapor deposition synthesis of periodic structures in the form of single-crystal diamond–SiO2 nanosphere composites, which exhibit the properties of photonic crystals in the visible spectral range, are reported. [ABSTRACT FROM AUTHOR]

NAD(P)+-dependent formate dehydrogenase (FDH, EC 1.2.1.2.) catalyzes the oxidation of formate ion with the coupled reduction of NAD(P)+ to NAD(P)H. Previously, in our laboratory, a genetic construct was obtained with the soyfdh2 gene encoding isoenzyme 2 of formate dehydrogenase from soybean Glycine max (SoyFDH). In this construct the nucleotide sequence encoding the signal peptide responsible for the transport of the pro-enzyme into the mitochondria of plant cells (the SoyFDH_L enzyme) was deleted. In this work, a second variant of SoyFDH_S was obtained, in which, compared to SoyFDH_L, the sequence at the N-terminus was reduced and changed to mimic the N-terminus sequence in FDH from Pseudomonas sp.101 bacterium. Next, a sequence of six histidine residues (His-tag) was added to the N-terminus of the long and short forms of SoyFDH. All four SoyFDH variants were expressed in E. coli BL21(DE3)CodonPlus cells. These enzymes were purified, their kinetic parameters were determined, and thermal stability was studied. In the case of SoyFDH_L, which is similar to the natural form of the enzyme, both variants, with and without His-tag, the expression level is two times higher compared to the truncated variant. The addition of His-tag to the N-terminus of enzymes reduces the level of expression. Changing the sequence of the N-terminus, as well as introducing the His-tag sequence to the N-terminus, does not significantly affect thermal stability of the enzymes at temperatures of 50–56°C. However, due to the higher values of the activation enthalpy ΔH≠ of the thermal inactivation process, the shortened form at normal temperatures is 3 times more stable than the natural one. A comparison of the kinetic parameters of the two SoyFDH variants shows that the catalytic constants are the same, but the long version SoyFDH_L has lower values , and the short version SoyFDH_S has lower values. The introduction of His-tag into the N-terminus of enzymes does not affect their kinetic parameters. [ABSTRACT FROM AUTHOR]

NAD(P)+-dependent formate dehydrogenase (EC 1.2.1.2, FDH) catalyzes the simplest reaction from chemical and biological points of view, oxidation of formate-ion to carbon dioxide coupled to NAD(P)+ reduction to yield NAD(P)H. Advances in the life sciences have shown that this reaction plays an extremely important role in a wide variety of organisms. The areas and types of practical applications of FDH are also permanently expanding. The review analyzes the key steps in the development of our knowledge on the role of formate dehydrogenase in living systems. Achievements in creation of highly efficient catalysts based on FDH for classic biotechnology as well as for new areas are also considered. The importance of a correct selection of the starting FDH form for the purpose of a biocatalyst design with required properties with minimal costs is demonstrated. The prospects for the use of FDH for CO2 fixation of CO2 are discussed. [ABSTRACT FROM AUTHOR]

The object of study is an electron gun with a desorption slit cathode and the Lewis pulse transformer at a voltage reaching 300 kV. The beam current and the input transformer voltage are measured in each pulse of the gun. By solving the equations describing the electrical circuit of the electron gun, spectral characteristics of the electron beam corresponding to the specific electrical parameters of the gun are obtained. Measurements using a magnetic spectrometer showed satisfactory agreement of the energy characteristics obtained during calculations and direct measurements. [ABSTRACT FROM AUTHOR]

Our earlier annotation of the genome of the yeast Ogataea parapolymorpha DL-1 made it possible to identify five genes of potential D-amino acids oxidases. All opadaao1–opadaao5 genes were cloned and expressed in E. coli. Four OpaDAAO1-OpaDAAO4 enzymes were obtained in highly purified form and their catalytic properties were studied. It was found that among all DAAO described in the literature, the enzyme OpaDAAOl has the highest catalytic constant kcat with D-Ala, which makes it promising for practical applications. However, in addition to good catalytic parameters, effective application of the enzyme in practice requires stability and knowledge of the inactivation mechanism, including at elevated temperatures. In this paper, we study the effect of elevated temperatures on the stability of OpaDAAOl. The enzyme is shown to have higher thermal stability than the majority of other D-amino acid oxidases. The kinetics of OpaDAAOl inactivation at different temperatures, at the initial concentrations of the enzyme, and in the presence of exogenous FAD are studied. A possible kinetic scheme of inactivation is proposed based on the data obtained. [ABSTRACT FROM AUTHOR]

NAD+-dependent formate dehydrogenase (EC 1.2.1.2, FDH) from pathogenic bacterium Staphylococcus aureus (SauFDH) differs significantly from other FDHs both in terms of primary structure and catalytic properties. A distinctive feature of SauFDH is the highest (about 2.5–3 times) specific activity compared to other formate dehydrogenases. At the same time, SauFDH has high Michaelis constants for both substrates. Based on the analysis of three-dimensional structures and the alignment of amino acid sequences, replacements promising in terms of changing catalytic parameters were selected. The replacement of I220H resulted in an increase in ; the value of kcat has not changed. When T250H is replaced, an increase in is observed, kcat decreases from 20 to 13 s–1. The replacement of K368H led to a slight increase in , kcat decreased from 20 to 6 s–1. The introduction of TGA and AGA additional inserts in α-helix at the C-terminus of the enzyme led to an increase in and . A bigger effect was observed for —the difference was more than 10 times. For mutant SauFDH with insertions kcat significantly reduced to 4 s–1. Similar results were observed for mutants with multipoint replacements. Thus, the C-terminal sequence has been shown to play an important role in the catalysis of SauFDH. [ABSTRACT FROM AUTHOR]

NAD+-dependent formate dehydrogenase (FDH, EC 1.2.1.2) from methylotrophic bacterium Pseudomonas sp.101 (PseFDH) has one of the highest thermal stability among all known enzymes of this group. The introduction of a number of amino acid substitutions into PseFDH made it possible to obtain a multipoint mutant PseFDH SM4S enzyme with even higher temperature and chemical stability. Previously, we showed that the introduction of additional single point replacements S131A, or S160A, or E170D into PseFDH SM4S led to further stabilization of the enzyme. In this work, based on the PseFDH SM4S S131A mutant, new mutant FDHs obtained, in which, compared to PseFDH SM4S, we added double S131A/E170D (M2), triple S131A/S160A/E170D (M3) and quadruple S131A/S160A/E170D/S145A (PseFDH SM4A M3) amino acids replacements. The new PseFDH mutants were overexpressed in E. coli cells, purified and characterized. The S131A/E170D and S131A/S160A/E170D changes provided further improving thermal stability. The introduction of the S145A substitution into PseFDH SM4A M3 leads to a significant decrease in and while maintaining the catalytic constant at the same level. This mutant form can be successfully used in NADH regeneration systems, as well as for the detection of NAD+ and formate in biological systems. [ABSTRACT FROM AUTHOR]

D-amino acid oxidase (DAAO) plays an important role in the functioning of both prokaryotes and eukaryotes. DAAO is increasingly being used in practice, including for the determination of D-amino acids in complex samples, involving human tissues and fluids. There are generally two types of DAAO in all organisms. The first type is an enzyme highly specific for D-aspartate and has its own name D-aspartate oxidase (DASPO). DAAO of the second type is characterized by a wide spectrum of substrate specificity, with preference for one or another D-amino acid varying from source to source. The activity of DAAO with a large number of substrates greatly complicates the selective determination of a particular D-amino acid. The problem is often solved by choosing an enzyme that, under the conditions of analysis, has low or no activity with other D-amino acids present in the sample. For the convenience of selecting a particular enzyme, we have collected and analyzed literature data on the catalytic parameters of known DAAOs with the most important D-amino acids. In addition, similar data are presented for novel recombinant DAAOs from the methylotrophic yeast Ogataea parapolymorpha DL-1. Analysis of the data shows that, with the D-amino acid series, the new OpaDASPO and OpaDAAO have the highest catalytic parameters. [ABSTRACT FROM AUTHOR]

NAD+-dependent formate dehydrogenase (FDH, EC 1.2.1.2) from bacterium Staphylococcus aureus (SauFDH) is the most active enzyme among FDHs of this group; however, the high values of KM of the enzyme with NAD+ and formate in the standard 0.1 M phosphate buffer result in lower catalytic efficiency kcat/KM than for other FDHs. Here, we study the effect of different buffers on the catalytic properties of SauFDH. Sodium phosphate (NaPB) is used as the base buffer component and Tris, Gly and citrate (Cit) are added to NaPB to prepare double, ternary, and quaternary buffer systems with different concentrations. It is found that KM for formate does not depend on the buffer composition and concentration, while the values of kcat and increase and decrease significantly. The highest positive effect is achieved in the case of quaternary buffer NaPB-Cit-Tris-Gly. At a 0.05 M concentration of each component, kcat increases by 70% compared to one in the standard 0.1 M NaPB. At a 0.1 M of each component, improvement in both parameters, kcat and , is observed. Thermal inactivation studies in NaPB and the complex NaPB-Cit-Tris-Gly buffer showed that at component concentrations of 0.1 M and more, SauFDH's thermal stability increased. The value of the stabilization effect depends on the ion strength but not on the type of buffer. A comparison of the X-ray structures of holo-forms of SauFDH and FDH from bacterium Pseudomonas sp.101 shows that the active site of PseFDH in complex with the substrate is totally closed, while in holo-SauFDH, amino acid residues in the active site can be accessed by water molecules and buffer components. This could be the reason of the kcat and changes in buffers of different compositions. [ABSTRACT FROM AUTHOR]

Phenylacetone monooxygenase from Thermobifida fusca (EC 1.14.13.92, PAMO) belongs to the Baeyer–Villiger family of monooxygenases and catalyzes the oxidation of various aromatic ketones to the corresponding esters using NADPH as a cofactor. In this study we analyzed the structure of the cofactor binding site, selected the most important amino acid residues for recognition of the phosphate group of the cofactor, and simulated enzyme structures with amino acid substitutions that could potentially lead to a change in the coenzyme specificity of the enzyme from NADPH to NADH. Based on the modeling, the most promising amino acid substitutions, T218D, T218E, K336A, and K336R, were proposed. Using site-directed mutagenesis we obtained genetic constructs containing genes encoding PAMOs with the corresponding amino acid substitutions, and the enzymes were expressed and purified. The resulting mutant PAMOs are able to bind NADH, but lack the ability to catalyze the oxidation of benzylacetone in the presence of NADH and show a deterioration of the Michaelis constants for NADPH. The catalytic constants of the mutant enzymes studied decrease slightly, and remain within the allowed experimental error. [ABSTRACT FROM AUTHOR]

We study Ge-doped polycrystalline diamond films synthesized, using microwave plasma chemical vapor deposition (CVD) in CH4-H2 base mixtures. We compare two sources of the dopant – gaseous monogermane (GeH4) and solid Ge plates. We investigate the structure and phase composition of the obtained films, using scanning electron microscopy, photoluminescence (PL), and Raman spectroscopy. We vary the precursor gas composition to maximize the intensity of the Germanium–vacancy (Ge-V) PL signal at 602 nm and discover that, using [C]-rich gas mixtures ([CH4]=20%), we are able to increase the intensity of Ge-V signal by two orders of magnitude in comparison with Ge-doped high-quality microcrystalline films of the same thickness but grown at [CH4]=4%. The attained results may be used for the fabrication of polycrystalline diamond films and plates with high concentrations of Ge-V centers, which may serve as source material for the fabrication of submicrometer-sized luminescent diamond particles for local optical thermometry. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs) are amongst the costliest natural hazards for southwest Pacific (SWP) Island nations. Extreme winds coupled with heavy rainfall and related coastal hazards, such as large waves and high seas, can have devastating consequences for life and property. Effects of anthropogenic climate change are likely to make TCs even more destructive in the SWP (as that observed particularly over Fiji) and elsewhere around the globe, yet TCs may occur less often. However, the underpinning science of quantifying future TC projections amid multiple uncertainties can be complex. The challenge for scientists is how to turn such technical knowledge framed around uncertainties into tangible products to inform decision-making in the disaster risk management (DRM) and disaster risk reduction (DRR) sector. Drawing on experiences from past TC events as analogies to what may happen in a warming climate can be useful. The role of science-based climate services tailored to the needs of the DRM and DRR sector is critical in this context. In the first part of this paper, we examine cases of historically severe TCs in the SWP and quantify their socio-economic impacts. The second part of this paper discusses a decision-support framework developed in collaboration with a number of agencies in the SWP, featuring science-based climate services that inform different stages of planning in national-level risk management strategies. [ABSTRACT FROM AUTHOR]

Resonant modes with frequencies 0.02–10 mHz are detected from the bow shock (BS) to the outer magnetosphere, with the nature of the resonances at frequencies 0.02–0.25 mHz being still unexplained. We propose a BS model in the form of a circular plate free along the outer edge that predicts resonant modes at frequencies 0.02–0.3 mHz or lower. We demonstrate the detection of these model resonant modes based on data from five satellites, with the resonance near 0.1 mHz predicted by the model being observed in the magnetosheath continuously for 17 hours downstream of both parallel and perpendicular shocks. Resonant BS modes produce three-wave nonlinear cascades that realize a broadband coherent coupling with resonances both near and inside the magnetopause. In our opinion, it is the coherent nature of the processes in an extended region with different linear resonant eigenmodes that determines the fairly new, nonlinear-cascade, approach to an efficient conversion of the energy of an inflow when interacting with an obstacle. This seems important for the entire nonlinear physics. We also provide arguments suggesting the possibility of resonant mode self-generation in the closed BS/magnetopause loop with a feedback in the form of narrow Poynting vector pulses at the cost of solar wind energy. [ABSTRACT FROM AUTHOR]

The interaction of a heavy-ion beam with matter is a fundamental problem of plasma physics and high-energy density in matter physics. The paper presents the results of experimental studies of energy losses of Fe+2 ions with an energy of 100 keV/u in a hydrogen plasma. The experimental data of plasma free electron stopping power are compared with theoretical models. [ABSTRACT FROM AUTHOR]

Southwest Pacific nations are among some of the worst impacted and most vulnerable globally in terms of tropical cyclone (TC)-induced flooding and accompanying risks. This study objectively quantifies the fractional contribution of TCs to extreme rainfall (hereafter, TC contributions) in the context of climate variability and change. We show that TC contributions to extreme rainfall are substantially enhanced during active phases of the Madden–Julian Oscillation and by El Niño conditions (particularly over the eastern southwest Pacific region); this enhancement is primarily attributed to increased TC activity during these event periods. There are also indications of increasing intensities of TC-induced extreme rainfall events over the past few decades. A key part of this work involves development of sophisticated Bayesian regression models for individual island nations in order to better understand the synergistic relationships between TC-induced extreme rainfall and combinations of various climatic drivers that modulate the relationship. Such models are found to be very useful for not only assessing probabilities of TC- and non-TC induced extreme rainfall events but also evaluating probabilities of extreme rainfall for cases with different underlying climatic conditions. For example, TC-induced extreme rainfall probability over Samoa can vary from ~ 95 to ~ 75% during a La Niña period, if it coincides with an active or inactive phase of the MJO, and can be reduced to ~ 30% during a combination of El Niño period and inactive phase of the MJO. Several other such cases have been assessed for different island nations, providing information that have potentially important implications for planning and preparing for TC risks in vulnerable Pacific Island nations. [ABSTRACT FROM AUTHOR]

The linear and nonlinear resonances and cascades affecting significantly the interaction of a collisionless plasma flow with a magnetic barrier and the plasma penetration into the barrier are studied using the near-Earth magnetopause as an example. Our linear theory of the membrane instability of the boundary of a magnetic barrier, the magnetopause, explains the structure of the spectra and bi-spectra of fluctuations on different segments of the boundary layers near the magnetopause and the resonances at frequencies 0.05–0.5 mHz. The recorded compressibility of waves under the magnetopause implies that their excitation by Alfv'en resonances alone is impossible. We assume, as a general principle, an approximate coincidence of the frequencies of different harmonics of different resonances as a condition for the amplification of resonances to nonlinear amplitudes and their propagation into the ionosphere. We confirm the presence of resonant waves near the magnetopause and demonstrate a nonlinear three-wave cascade interaction of compressible (0.05–5 mHz) and incompressible waves under the magnetopause that provides the excitation of resonances of magnetic field lines and waveguide resonances at frequencies 1–25 mHz without a close coincidence of the frequencies with linear resonances at the magnetopause and the bow shock. This can also provide a nonlinear coupling of linear and nonlinear resonances in other multilayered media (for example, in the plasma and neutral sheets of the geomagnetic tail and between it and the magnetopause). An example of the excitation of a waveguide mode inside the magnetopause by nonlinear membrane waves is given. We have detected a nonlinear excitation and interaction of most "magic" harmonics under the magnetopause. [ABSTRACT FROM AUTHOR]

NAD+-dependent formate dehydrogenase from thermotolerant yeast Ogataea parapolymorpha DL-1 (OpaFDH, EC 1.2.1.2) with the additional N-terminal Gly residue and its double mutant OpaFDH_AD were overexpressed in E. coli cells. The enzyme yield was, respectively, 6000 and 6200 units per liter of the cultivation medium. Purified enzymes were obtained as homogeneous preparations with a yield of 62%. The purification procedure included ultrasonic cell disruption, heat treatment of cell free extracts at 55°C for 15 min, and hydrophobic chromatography on the Phenyl Sepharose Fast Flow. Crystallization experiments with wild-type OpaFDH resulted in the preparation of crystals of the apo-form but not the holo-form. Crystals of the holo-form were prepared in the case of the OpaFDH_AD mutant in the presence of 7 mM NAD+ and 10 mM sodium azide. The size and quality of the crystals are sufficient to collect X-ray diffraction data and determine the enzyme three-dimensional structure. [ABSTRACT FROM AUTHOR]

NAD(P)+-dependent formate dehydrogenase (FDH, EC 1.2.1.2.) is actively used in processes of chiral synthesis by oxidoreductases with systems of reduced cofactor regeneration. The efficient use of FDH in such systems requires simple and fast enzyme purification. Metal-chelate affinity chromatography is widely used for such purposes. The method requires the presence of at least six His residues at N- or C-terminus of protein. The addition of extra His residues can affect enzyme properties. The computer modeling of the structure of FDH from bacterium Pseudomonas sp. 101 with different positions of His6 sequence showed that the optimal case is His-tag at N-terminus. Three types of PseFDH with His6 were prepared: wild-type NAD+-dependent enzyme and two mutant NADP+-specific forms. New PseFDHs were obtained as homogeneous preparations through a one-step purification procedure. The comparison of PseFDHs with and without His-tag showed that they have similar kinetic properties. [ABSTRACT FROM AUTHOR]

Currently, work is underway to create laser accelerators with beam focusing by plasma lenses. For effective focusing, it is necessary to investigate at which initiation of breakdown a discharge forms with a more uniform distribution of current density. Our studies have shown that the plasma distribution is uniform over a longer period of time, including the region of maximum current, if the discharge is initiated by an electron beam. [ABSTRACT FROM AUTHOR]

NAD+-dependent formate dehydrogenase from Staphylococcus aureus (SauFDH) is one of the key enzymes responsible for the survival of this pathogen in the form of biofilms. 3D structure of the enzyme might be helpful in the search for highly specific SauFDH inhibitors that can be used as antibacterial agents exactly against S. aureus biofilms. Here, we prepared a recombinant SauFDH in Escherichia coli cells with a yield of 1 g target protein per liter medium. The developed procedure for the enzyme purification allowed to obtain 400 mg of homogenous enzyme with 61% yield. The specific activity of the purified recombinant SauFDH was 20 U per mg protein, which was 2 times higher than the previously reported activities of formate dehydrogenases. We also found crystallization conditions in the course of two rounds of optimization and obtained 200- and 40-µm crystals for the SauFDH apo- and holoenzymes, respectively. X-ray analysis using synchrotron X-ray sources produced diffraction data sufficient for solving the three-dimensional structures of the apo- and holoenzymes with the resolution of 2.2 and 2.7 Å, respectively. Crystals of the apo- and holoforms of SauFDH had different crystal space groups, which suggest coenzyme binding in the SauFDH holoenzyme. [ABSTRACT FROM AUTHOR]

A polycrystalline diamond film is grown on a 2 inch Si substrate using a microwave-plasma chemicalvapor-deposition technique. The high quality of the diamond films is confirmed by Raman spectra. A multiple-step procedure is used for local etching of the substrate to form the pattern of an array of 50 diamond membranes with the diameter in a range from 150 to 300 μm. The morphology of the membranes is examined using scanning electron microscopy. The membranes obtained can be used as the base material for the fabrication of pressure sensors, X-ray detectors and scintillators, and in quantum optics as optical resonators for single-color centers in diamond. [ABSTRACT FROM AUTHOR]

Phenylacetone monooxygenase (EC 1.14.13.92, PAMO) catalyzes oxidation of ketones with molecular oxygen and NADPH with the formation of esters. PAMO is a promising enzyme for biotechnological processes. In this work, we generated genetic constructs coding for PAMO from Thermobifida fusca, containing N- or C-terminal His6-tags (PAMO N and PAMO C, respectively), as well as PAMO L with the His6-tag attached to the enzyme C-terminus via a 19-a.a. spacer. All PAMO variants were expressed as catalytically active proteins in Escherichia coli BL21(DE3) cells; however, the expression level of PAMO N was 3 to 5 times higher than for the other two enzymes. The catalytic constants (kcat) of PAMO C and PAMO L were similar to that published for PAMO L produced in a different expression system; the catalytic constant for PAMO N was slightly lower (by 15%). The values of Michaelis constants with NADPH for all PAMO variants were in agreement within the published data for PAMO L (within the experimental error); however, the KM for benzylacetone was several times higher. Thermal inactivation studies and differential scanning calorimetry demonstrated that the thermal stability of PAMO N was 3 to 4 times higher compared to that of the enzymes with the C-terminal His6-tag. [ABSTRACT FROM AUTHOR]

Simulations and projections of the El Niño Southern Oscillation's (ENSO's) influence on TC track variability was analysed globally using Coupled Model Intercomparison project Phase 5 (CMIP5) models. The ability of these models to simulate the historical (1970–2000) ENSO–TC track relationship and inform us of the likely projected changes resulting from high carbon emissions (RCP8.5) in a climate projection (2070–2100) was determined through cluster analysis. The number of seasonal TC occurrences during traditional ENSO events ("El Niño" and "La Niña") in each cluster were used to determine whether each cluster was "El Niño dominant", "La Niña dominant" or "neither". Only seven out of a combined total of 28 clusters across all basins were found to disagree in terms of "ENSO dominance" between the observed records and historical model simulations. This suggests that models can simulate the ENSO and TC track relationship reasonably well. Under sustained high carbon emissions, La Niña TCs were projected to become dominant over El Niño TCs in the central South Indian Ocean (~ 60–100°E), the southern Bay of Bengal and over straight-moving TCs in the South China Sea. El Niño TCs were projected to increase and become dominant over La Niña TCs in a larger area of the western South Pacific (~ 160°E–165°W) and central North Pacific (~ 160°E–145°W) Oceans. Projections of track directions and lifetimes, while less robust, indicated that El Niño TCs would track westward more often in the Coral Sea (150–165°E), while El Niño TCs that took an eastward track here would have longer lifetimes (~ 3 days). [ABSTRACT FROM AUTHOR]

The sensitivity of tropical cyclone (TC) projection results to different models and the detection and tracking scheme used is well established in the literature. Here, future climate projections of TC activity in the Eastern North Pacific basin (ENP, defined from 0° to 40°N and 180° to ~ 75°W) are assessed with a model- and basin-independent detection and tracking scheme that was trained in reanalysis data. The scheme is applied to models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) experiments forced under the historical and Representative Concentration Pathway 8.5 (RCP8.5) conditions. TC tracks from the observed records and models are analysed simultaneously with a curve-clustering algorithm, allowing observed and model tracks to be projected onto the same set of clusters. The ENP is divided into three clusters, one in the Central North Pacific (CNP) and two off the Mexican coast, as in prior studies. After accounting for model biases and auto-correlation, projection results under RCP8.5 indicated TC genesis to be significantly suppressed east of 125°W, and significantly enhanced west of 145°W by the end of the twenty-first century. Regional TC track exposure was found to significantly increase around Hawaii (~ 86%), as shown in earlier studies, owing to increased TC genesis, particularly to the south-east of the island nation. TC exposure to Southern Mexico was shown to decrease (~ 4%), owing to a south-westward displacement of TCs and overall suppression of genesis near the Mexican coastline. The large-scale environmental conditions most consistent with these projected changes were vertical wind shear and relative humidity. [ABSTRACT FROM AUTHOR]

The sunward Poynting flux throughout the magnetosheath and foreshock (directly measured by INERBALL-1, CLUSTER-4, and DOUBLE STAR TC1) and its correlation and bi-correlation with the dynamic pressure of the solar plasma flow have been analyzed. It has been demonstrated for the first time that perturbations caused by resonances in the magnetospheric boundary layers propagate upstream towards the bow shock as the short impulses of the sunward Poynting flux, which excite the strongest three-wave resonances. They are initiated in the foreshock and regulate the bow shock surface oscillations. Another interaction zone near the magnetopause assists plasma flow extra deflection and acceleration around the magnetopause. At the outer boundary of stagnant cusp the turbulent barrier can separate the flowing and stagnant plasmas namely by the three-wave cascades. Therefore, both experiment and magnetohydrodynamic simulation demonstrate the leading role of the discovered waves and nonlinear processes in the collisionless interaction of the plasma flow and magnetic barrier. [ABSTRACT FROM AUTHOR]

The oxidation of cephalosporin C (CPC) by D-amino acid oxidase is the first stage in the biocatalytic industrial process of the production of 7-aminocephalosporanic acid, the initial synthon for the production of semisynthetic cephalosporin antibiotics. We determined the kinetic parameters (catalytic constant rate and Michaelis constant) of the wild-type recombinant oxidase from the yeast Trigonopsis variabilis (TvDAAO); three mutant forms of the enzyme with point Met-to-Leu substitutions at positions 104, 156, and 209; and the TvDAAO RDAF quadruple mutant using the dependence of the initial reaction rate on the CPC concentration (the initial rate method). The point substitutions in the mutants are shown to lead primarily to a decrease in the Michaelis constant. The largest (39%) increase in catalytic efficiency kcat/KM is observed for the mutant with the Met156Leu substitution. The Michaelis constant for the increased four times compared to that for the wild-type enzyme in the reaction with CPC, whereas the catalytic efficiency remains almost unchanged due to a four-fold increase in the catalytic rate constant. [ABSTRACT FROM AUTHOR]

A recently validated algorithm for detecting and tracking tropical cyclones (TCs) in coarse resolution climate models was applied to a selected group of 12 models from the Coupled Model Intercomparison Project (CMIP5) to assess potential changes in TC track characteristics in the Southern Hemisphere (SH) due to greenhouse warming. Current-climate simulations over the period 1970–2000 are first evaluated against observations using measures of TC genesis location and frequency, as well as track trajectory and lifetime in seven objectively defined genesis regions. The 12-model (12-M) ensemble showed substantial skill in reproducing a realistic TC climatology over the evaluation period. To address potential biases associated with model interdependency, analyses were repeated with an ensemble of five independent models (5-M). Results from both the 12-M and 5-M ensembles were very similar, instilling confidence in the models for climate projections if the current TC-climate relationship is to remain stationary. Projected changes in TC track density between the current- and future-climate (2070–2100) simulations under the Representatives Concentration 8.5 Pathways (RCP8.5) are also assessed. Overall, projection results showed a substantial decrease (~ 1–3 per decade) in track density over most parts of the SH by the end of the twenty-first century. This decrease is attributed to a significant reduction in TC numbers (~ 15–42%) consistent with changes in large-scale environmental parameters such as relative vorticity, environmental vertical wind shear and relative humidity. This study may assist with adaption pathways and implications for regional-scale climate change for vulnerable regions in the SH. [ABSTRACT FROM AUTHOR]

The use of polycrystalline diamond in optics (transparent windows) and electronics (heat sinks) usually requires polishing of a synthesized wafer. However, mechanical polishing of diamond faces certain difficulties, since it is a material with a record high hardness. In this study, we propose a new approach to forming low-roughness diamond layers by periodic time-limited adding (injection) of nitrogen into the standard methane‒hydrogen (CH4–H2) gas mixture. Nitrogen stimulates secondary nucleation on the formed well-faceted micrometer diamond grains, which prevents their further growth. The transition from a continuous supply of N2 to short-term injections prevents the formation of continuous nanocrystalline diamond layers and makes it possible to grow high-quality microcrystalline diamond layers between the nitrogen injection periods. [ABSTRACT FROM AUTHOR]

A lot of activities are carried out to develop compact laser accelerators. The transportation and focusing of beams in Z-pinch-type discharges, which requires thorough investigations into methods for the formation of these discharges, are important problems to be solved. At the ITEP, an experimental setup [1] is constructed to study Z-pinch plasma dynamics when the discharge is initiated by an electron beam. The first results of the experimental and numerical investigations show that development of the discharge initiated by an electron beam differs considerably from the ordinary Z-pinch formation process. [ABSTRACT FROM AUTHOR]

Abstract: We prepared thin films containing colloidal quantum dots CdSe/ZnS of four different mean core sizes, with photoluminescence maximum in the range 530-610 nm, and covered by different ligands, on the surface of water by the Langmuir method. We obtained Surface pressure-Area curves (π-A isotherms) of the formed films at room temperature under different conditions: the compression speed and the waiting time before the film was compressed. In the course of the studies, we established that the type of ligand that passivates the surface of the quantum dots greatly influences the formation of CdSe/ZnS Langmuir films, and that the compression speed and the waiting time before the film is compressed do not seriously affect the formation of the films. [ABSTRACT FROM AUTHOR]

The effect of medium pH and ion strength on the thermal stability of formate dehydrogenases (EC 1.2.1.2, FDH) from model plant Arabidopsis thaliana (AthFDH) and soybean Glycine max (SoyFDH) are studied. The dependence of the residual activity on time is described by the kinetics of the reaction of the first order in all the experimental conditions. The dependence of the first order thermal inactivation constants on phosphate buffer concentration has the form of a bell-shaped curve. It was found that an increase in the pH value resulted in an increase and decrase of inactivation rate constans for SoyFDH and AthFDH, respectively. The activation parameters of the thermal inactivation process, ΔH≠ and ΔS≠ are calculated from the experimental data at different medium pH values and phosphate buffer concentrations. [ABSTRACT FROM AUTHOR]

Formate dehydrogenases (FDHs) from different sources are systematically studied in our laboratory. Over the past few years, new genes of four FDHs from pathogenic bacterium Staphylococcus aureus (SauFDH), methylotrophic thermotolerant yeast Ogataea parapolymorpha (OpaFDH), yeast Saccharomyces cerevisiae (SceFDH), and moss Physcomitrella patens (PpaFDH) have been cloned and expressed in E. coli cells. By means of differential scanning calorimetry, a comparative study of thermal stability of new recombinant formate dehydrogenases and a number of FDHs from other sources has been performed. It was shown that two new enzymes, SauFDH and OpaFDH, are comparable to the FDH from Pseudomonas sp. 101 bacteria in their stability. SceFDH is the least stable FDH among the described formate dehydrogenases. [ABSTRACT FROM AUTHOR]

The data of the turbidimetric measurement for the enzymatic lysis of various living bacterial cells are analyzed. A method for the correct recalculation of the turbidimetric data (-ΔA/Δt) into absolute values of the change in the concentration of living cells (-ΔCFU/Δt) is proposed. The dimensionless efficiency of cell lysis-(1/CFU0) · ΔCFU/Δt for various bacterial cells is calculated to correctly compare the efficiency of the action of different bacteriolytic factors on various bacterial cells. [ABSTRACT FROM AUTHOR]

Research building B at the Bochvar High-Technology Research Institute for Inorganic Materials (VNIINM) located within the city limits of a dense residential development was decommissioned in 2013-2015. Radioactively contaminated equipment and utility services were disassembled and removed, building structures were decontaminated, the framework was dismantled, the grounds of the development site were restored, and radioactive waste was transferred to specialized organizations. The framework was liquidated in strict accord with the norms and regulations governing the use of atomic energy. [ABSTRACT FROM AUTHOR]

Majority of native enzymes are poorly applicable for practical usage: that is why different methods of enzyme modification are used to obtain the biocatalysts with appropriate characteristics. Development of genome sequencing and various modern approaches in protein engineering allow one to identify protein of interest and to improve the enzyme properties for a particular process. This review describes the results on development of novel biocatalysts based on bioinformatics and rational design. New genes encoding formate dehydrogenase (FDH) from bacterium Staphylococcus aureus, yeasts Ogataea parapolymorpha and Saccharomyces cerevisiae and moss Physcomitrella patens (SauFDH, OpaFDH, SceFDH and PpaFDH, respectively), have been cloned. New FDHs were produced in the active form and characterized. SauFDH was shown to have at least 2-fold higher catalytic constant than other known FDHs. OpaFDH has catalytic parameters as good as those for soy FDH mutant forms, and in addition, is more thermostable. Apo- and holo-forms of SauFDH have been crystallized. Mutation of two Cys residues in Pseudomonas sp.101 enzyme (PseFDH) yields enzyme preparations with improved kinetic parameters and enhanced thermal and chemical stability. New generation of PseFDH preparations with the coenzyme specificity changed from NAD+ to NADP+ have been obtained. The effect of ionic liquids on the catalytic properties and thermal stability of six wild-type recombinant FDHs, and a number of their mutants, have been studied. In case of D-amino acid oxidase (DAAO), single-point mutations have been combined to create multi-point mutants. The introduced amino acid replacements have been shown to exert an additive effect, improving both kinetic parameters and increasing thermal and chemical stability. DAAO genes from Hansenula polymorpha yeast have been cloned. α-Amino acid ester hydrolase (AEH) gene has been cloned and expressed in the active form in E. coli. Structural modeling has been performed and the effectiveness in amino beta-lactams synthesis studied. The structure of a single-chain penicillin acylase from Alcaligenes faecalis (scAfPA) has been modeled and two variants of scAfPA gene was generated by PCR. Both variants have been expressed in E. coli, isolated and characterized. Catalytic properties of scAfPA were slightly better than those of its natural heterodimer. [ABSTRACT FROM AUTHOR]

This paper considers the motion of a five-link crawling robot equipped with special friction elements for the periodic clamping of the links along a rough horizontal surface. A classification of the modes of motion depending on the presence of obstacles on the surface and ways of crossing them is presented. One of the crawling modes along the surface without obstacles or with obstacles when the end links are detached from the surface and the adjacent ones rotate by a given angle in the motion plane is analyzed. The influence of the control parameters on the average robot speed is established. [ABSTRACT FROM AUTHOR]

The exoskeleton of the lower limbs is considered and the problem of increasing its energy efficiency is solved. The problem of nonlinear optimization is stated. The coefficients of the exoskeleton control system regulator act as optimized parameters. The target function is selected so that the optimal set of coefficients provides high accuracy of operation of the control system and its energy efficiency. A numerical method of solving the optimization problem is described and the simulation results are presented. [ABSTRACT FROM AUTHOR]

D-amino acid oxidase (DAAO) is an FAD-containing oxidoreductase that stereospecifically oxidases D-amino acids to produce α-keto-acids, an ammonium ion, and hydrogen peroxide. The most important biotechnological process involving DAAO is the production of 7-amino cephalospranic acid (7-ACA) from cephalosporin C. The reaction product, 7-ACA, is then used as a precursor for the synthesis of cephalosporin antibiotics of different generations. We previously obtained mutant DAAOs from the yeast Trigonopsis variabilis (TvDAAO). The mutants with point amino acid substitutions were characterized by either an increased thermal stability or improved catalytic properties in the oxidation of cephalosporin C. In the present study, we obtained two new mutant TvDAAOs with two and four amino acid substitutions, respectively. The catalytic constants of these mutant TvDAAOs for the oxidation of cephalosporin C were 1.8 and 4 times higher than the respective parameter of the wild-type enzyme (wt-TvDAAO). The combination of substitutions increased the thermal stabilities of both mutant TvDAAOs by a factor of 2-3 as compared with the wt- TvDAAO. [ABSTRACT FROM AUTHOR]

The theory of charged current sheets is compared with plasma data of Prognoz-8, Interball-1, Polar, and Cluster satellites. The possibility of momentum and energy transfer into the magnetosphere, irrespective of magnetic field line reconnection, as a specific dynamo effect, is shown. This relates statistical properties of the turbulent boundary layers with the character of the transfer through thin boundaries. [ABSTRACT FROM AUTHOR]

The expression of galectin-8 (gal-8) has been shown to be altered during neoplastic transformation of certain cell types. This is the first study aimed to analyze the expression of this protein in normal and pathological human thyroid tissue. A total of 41 archival thyroid tissue samples (5 follicular adenomas, 31 papillary carcinomas, 5 follicular carcinomas) together with 36 adjacent hyperplastic or normal thyroid tissues were analyzed by immunohistochemistry. Galectin-8 was expressed in the majority of papillary carcinomas (27/31; 87%). Positive but weaker staining was also found in some of the follicular thyroid carcinomas (2/5; 40%) and adenomas (2/5; 40%). This protein was not detectable in five normal thyroid tissue samples, whereas hyperplastic areas adjacent to tumor were weakly positive in 9 out of 31 cases (29%). High gal-8 immunostaining in papillary thyroid carcinoma indicates that gal-8 may potentially serve as a marker of papillary thyroid carcinoma. However, it does not seem to be helpful in the differential diagnostics of follicular carcinoma and adenoma. Further studies are required to determine biological functions and molecular mechanisms underlying the increased expression of gal-8 protein in thyroid lesions, particularly, in papillary thyroid carcinoma. [ABSTRACT FROM AUTHOR]

The effect of a dc electric field on strongly nonideal Coulomb systems consisting of a large number (~10) of charged diamagnetic dust particles in a cusp magnetic trap are carried out aboard the Russian segment of the International Space Station (ISS) within the Coulomb Crystal experiment. Graphite particles of 100-400 μm in size are used in the experiments. Coulomb scatter of a dust cluster and the formation of threadlike chains of dust particles are observed experimentally. The processes observed are simulated by the molecular dynamics (MD) method. [ABSTRACT FROM AUTHOR]

An installation is developed for studying the dynamics of Z-pinch plasma with the discharge initiation by an electron beam. Research and commissioning works are performed for creating a system of electron beam formation using the adiabatic plasma lens. The study results are presented. [ABSTRACT FROM AUTHOR]

The radiation status of the special ventilation and piping systems is investigated as part of the work on the preparation of building B at the Bochvar All-Russia Research Institute for Inorganic Materials for decommissioning. Methods for extracting samples have been developed. Analysis for the content of plutonium isotopes showed that the deposits and precipitates are medium-level wastes. [ABSTRACT FROM AUTHOR]

The oxidative stability of enzymes is mostly dependent on the stability of the Cys and Met residues. Three single point mutants with Met/Leu substitutions in D-amino acid oxidase (DAAO, EC 1.4.3.3) from the yeast Trigonopsis variabilis (TvDAAO) are prepared and characterized. The positions for the amino acid residue substitutions are selected based on multiple alignment of different DAAO amino acid sequences and analysis of the three-dimensional structure of TvDAAO. It is shown that the substrate specificity profile ischanged for all of the mutants. The K values for the small and bulky D-amino acidsare increased and decreased, respectively. One of the Met/Leu substitutions results in a two- to threefold increase in thermal stability as compared to the wild-type enzyme. A method for the determination of TvDAAO stability in the presence of hydrogen peroxide is developed and the oxidative stability of wild-type and mutant TvDAAOs is studied. It is shown that none of thethree mutations changes the oxidative stability of the enzymes. [ABSTRACT FROM AUTHOR]

Problems of simulating the processes of exoskeleton sit-to-stand movement are considered. A mathematical model of the device is described. The diagram of an automatic control system is proposed, based on the ZMP method. The results of the mathematical simulating are given. It is shown that the proposed control system makes verticalization possible without falling from a wide range of initial conditions. [ABSTRACT FROM AUTHOR]